1. Field of the Invention
The present invention relates to an air conditioning system, more particularly to an air conditioning system for a vehicle.
2. Description of the Related Art
The performance of equipment of an electric motor vehicle depends on the weather and the environment, and is relatively great when the equipment operates under a specified temperature range. For example, efficiency of a battery of the electric motor vehicle is significant for endurance of the electric motor vehicle, so that the battery should operate under a specified temperature range in order to maintain relatively greater efficiency thereof. However, an environment temperature surrounding the battery may affect the operation of the battery. Therefore, in the development of the electric motor vehicle, management and control of the temperature of the battery and the vehicle equipment are critical. Use of the air conditioning system for implementing the heat management of the battery and the vehicle equipment is currently a main focus in the industry.
Generally, electrical heating and water cooling are used in the conventional heat management of the battery for controlling the temperature of the battery, but these two methods both consume a lot of energy. There is also another method of controlling the temperature of the battery through ventilation, but such ventilation cannot effectively control the temperature of the battery. Regarding the heating system of the electrical motor vehicle, it is usually configured to heat the cabin by electrical heating. For the efficiency of the heat exchanger and the electrical heater of the heating system, it is required to consume additional electrical energy stored in the battery.
According to U.S. Patent Application Publication No. 2009/0249807, an HVAC and battery thermal management for a vehicle uses a coolant pump for pumping a coolant through a coolant loop for cooling a battery pack of a vehicle. Further, a battery internal heater or other suitable heater, such as a coolant heater in the coolant loop may be employed to heat the battery pack. Although this U.S. patent application discloses the HVAC and battery thermal management capable of providing relatively greater efficiency, an additional heater is required for heating the battery pack.
U.S. Pat. No. 5,878,589 discloses a vehicular air conditioning system for electric vehicles. In such vehicular air conditioning system, the waste heat generated from a heating part in a vehicle is recovered and extracted by a coolant for heat exchange while suppressing an increase in the power consumption. However, the layout of the vehicular air conditioning system is relatively complicated and is hard to be assembled.